CHARACTERIZATION OF POLY(ETHYLENE-TEREPHTHALATE) AND POLY(ETHYLENE-TEREPHTHALATE) BLENDS

Citation
B. Fox et al., CHARACTERIZATION OF POLY(ETHYLENE-TEREPHTHALATE) AND POLY(ETHYLENE-TEREPHTHALATE) BLENDS, Polymer, 38(12), 1997, pp. 3035-3043
Citations number
34
Categorie Soggetti
Polymer Sciences
Journal title
ISSN journal
00323861
Volume
38
Issue
12
Year of publication
1997
Pages
3035 - 3043
Database
ISI
SICI code
0032-3861(1997)38:12<3035:COPAP>2.0.ZU;2-U
Abstract
A method for the direct determination of the molecular weight of the p oly(ethylene terephthalate) (PET) component in PET/acrylonitrile-butad iene-styrene (ABS) blends by gel permeation chromatography has been de veloped. This technique has been applied to demonstrate that an observ ed deterioration in the mechanical properties (e.g. Izod impact streng th) of PET/ABS blends on processing can be correlated with a decrease in the molecular weight of the PET component. In the course of this wo rk, various methods for evaluating the molecular weight and chemical m icrostructure of PET were examined. The use of nuclear magnetic resona nce (n.m.r.) spectroscopy as a means of quantitatively identifying end groups and comonomers that are present at the 1-4% level in commercia l PET (e.g. diethylene glycol, cyclohexanedimethanol and isophthalic a cid) is critically evaluated with reference to the stability of PET an d PET end groups in various n.m.r. solvents. New H-1 n.m.r. chemical s hift assignments for cyclohexanedimethanol units are presented, and th e reactivity of hydroxy end groups in trifluoroacetic acid mixtures is examined. (C) 1997 Elsevier Science Ltd.